A flow rate adjustment device that adjusts a flow rate of liquid by changing the amount of intrusion of a needle valve body to a fluid-flow-path outlet that is opened to a valve seat has been conventionally known (e.g., see Japanese Unexamined Patent Application, Publication No. 2011-247378 (hereinafter referred to as “JP 2011-247378”)).
In the flow rate adjustment device disclosed in JP 2011-247378, a reciprocating movement section is installed in a casing provided with the fluid-flow-path outlet, and the reciprocating movement section converts rotational movement of a motor into vertical movement to thereby change the amount of intrusion of the needle valve body to the fluid-flow-path outlet.